Photocopy developer



April 25, 1967 B. D. EISNER ET Al.

PHOTOCOPY DEVELOPER FiledJune 28, 1962 INVENTORS D. ErsNER D. SAcRE BuRToN Leo United States Patent Oi ice 3,315,582 Patented Apr. 25, 1967 3,315,582 IHOTOCOPY DEVELOPER Burton D. Eisner, Highland Park, and Leo D. Sacre,

Prospect Heights, Ill., assignors to American Photocopy Equipment Company, Evanston, Ill., a corporation of Illinois Filed June 28, 1962, Ser. No. 205,973 Claims. (Cl. 95-89) This invention relates to a phtocopy developer apparatus for the production of photocopies by means of the so-called Diifusion Transfer process.

In the complete diffusion transfer process, the document or other material to 'be copied is first placed into face-to-face contact with `a negative sheet of photosensitive paper, and the two sheets are then exposed to light, usually by the reflex method, so as to form a latent photographic image on the negative sheet. The latter is then separated from the document and then immersed with a positive sheet in `a developer solution and subsequently passed together between a pair of line Contact rollers so as to cause the image to be transferred from the negative sheet to the positive sheet. The two sheets are then peeled apart and the image bearing positive sheet becomes a nal photocopy product.

The novel apparatus in accordance with the present invention is directed toward apparatus that can be ernployed to transfer a positive image onto a provided photocopy paper from a non-developed but exposed negative sheet.

In the prior art, this has been accomplished by providing a tank with developer liquid contained therein and maintained at a predetermined level. A pair of line contacting rollers are positioned adjacent one end of the developer tank and adapted to engage the positive and negative sheets as they are fed to the bite of the rollers so -as to thereafter cause the image to be transferred from the negative sheet to the positive sheet, and also to squeeze the positive and negative sheets together to remove any excess developer fluid therebetween. Positive guiding means extending from the opening end of the tank and down into and below the level of the liquid is provided to insure that a suicient amount of developer liquid will contact yand properly wet both the negative and positive sheets as they move through the developer tank. Further, in the prior art, guide means have been provided which extend from the entrance end ofthe developer tank all the way continuously to adjacent the bite of the rollers at the other end of the developer tank. In some cases, the guide means in the prior 'ait have been shortened so as not to extend all the Way to or adjacent the bite of the rollers at the opposite end of the developer tank, but nevertheless, all of the prior art has included positive guide means extending from above the level of the liquid at the entrance end of the developer tank and down to and below the level of the developer liquid in the tank, so `as to insure that the positive and negative sheets are contacted by suliicient developer liquid.

In the prior art, because the positive and negative sheets are fed into vthe developer tank in substantially parallel paths, it was necessary to provide guide means which extend below the level of the developer liquid in the tank to keep the positive yand negative sheets separated to insure thta they are properly wetted by a sufficient amount of developer liquid before the positive and negative sheets contact each other.

With the present invention, it has been found that by directing the positive and negative sheets into diverging paths as they are fed into the developer liquid in the tank, a suicient amount of developer liquid will Contact and properly wet the positive and negative sheets even though no guide means extending below the level of the liquid in the tank are provided for separating the two sheets.

The guide means for directing the positive and negative sheets into diverging paths before they reach the developer liquid in the developer tank, can be made of any of a large variety of materials, inasmuch as the guide means do not come in contact with the developer liquid itself. The positive and negative sheets are of sufiicient stiffness when dry to maintain themselves in diverging paths `after they have progressed past the diverging guide means.

After coming into contact and being wetted with the developer liquid, the sheets move to the bottom of the tank and travel along the bottom on each other, being guided through the developer by guide means provided on the bottom of the tank. No other guide means in the developer liquid is required. After emerging from the developer liquid, the sheets move into engagement with a roller-belt arrangement positioned above the level of the liquid where they are uniformly pressed together in an extended plane of contact to transfer the image from the negative sheet to the positive sheet and to remove any excess of developer liquid between the positive and negative sheets. The guide means formed on the bottom of the developer tank proves to be adequate for directing the sheets through the developer liquid to the bite of the roller-belt arrangement.

It is the general object of this invention to provide photocopy developer apparatus that is simple in construction, eicient in operation, and comparatively inexpensive to manufacture and which can be made of a variety of materials.

It is another object of this invention to provide photocopy developer apparatus including guiding means positioned above the level of the developer liquid and which is designed to direct the positive and negative sheets into diverging paths as they are fed into the developer liquid in the developer tank whereby the positive and negative sheets will be properly wetted by a suflicient amount of developer liquid before coming in contact with each other in the developer liquid.

It is another object of this invention to provide photocopy developer apparatus including a roller-belt arrangement positioned above the level of the developer liquid in the apparatus and which is designed to uniformly press the positive and negative sheets together in an extended plane of contact after the positive and negative sheets have traversed the developer tank so that a uniform image will be transferred from the negative sheet to the positive sheet.

Briefly, the invention relates to a developer apparatus for causing the transfer of a positi-ve image to a photocopy sheet from an undeveloped but exposed photocopy negative sheet and comprises: a developer tank adapted to hold liquid developer therein at a given level and having the inside bottom wall thereof shaped so as to guide photocopy sheets through the developer liquid; a roller-belt arrangement positioned adjacent the exit end of the developer tank and designed to uniformly press the photocopy sheets together in an extended plane of contact to cause a uniform transfer of the image from the negative sheet to the positive sheet and, at the same time, to expel any excess liquid developer solution from between the negative and positive sheets; and diverging guide means positioned above the level of the liquid in the developer tank and designed to control the paths of the photocopy sheets as they enter into and come in contact with the developer liquid to insure that the photocopy sheets are wetted by a sufficient amount of developer liquid as they travel through the developer tank.

Other advantages, objects and features of the invention will become more apparent if the following is viewed in light of the drawings of which:

FIG. 1 is a cross-sectional diagrammatic side view of one embodiment of the invention;

FIG. 2 is a cross-sectional -diagrammatic partial side view of a second embodiment of the invention; and

FIG. 3 is a cross-sectional diagrammatic side view Of a third embodiment of the invention.

Referring to FIG. 1 of the drawings, there is illustrated a developer housing 8 having positioned therein a developer tank 10 that is rectangular in configuration, and which has a width that exceeds the depth by several times. The bottom portion of the developer tank comprises a plurality of parallel spaced curved ribs 12 integrally formed in the tank 10 so as to, in conjunction with gravity, guide the bottom sheet N and the upper sheet P as they travel through the developer liquid in the developer tank 1t). It is not necessary that the bottom curved ribs 12 contact the sheets at each and every point and the exact shape of the curved ribs 12, although generally U-shaped, can be altered as dictated by the variables, such as the speed of travel of the sheets through the developer tank 1t), the type and thickness of the paper, etc. As seen in the drawings, the bottom curved ribs 12 of the developer tank 10 are somewhat U-shaped or curvilinear in shape. In more detail the bottom guide ribs 12 comprise a rst portion 71 extending downwardly and inwardly at the entrance, a second portion 73 extending upwardly and outwardly at the exit side thereof, and a substantially straight intermediate section 74 extending a substantial distance along the bottom surface of the tank and disposed substantially horizontally. The developer liquid is maintained at a predetermined level in the developer tank 10 by means not Shown. Any means, however, known to those skilled in the art may be utilized to maintain the developer liquid at a predetermined level in the developer tank 18.

Positioned at the exit end of the developer tan-k 10 is a roller-belt arrangement 2 through which the positive sheet P and the negative sheet N pass after transmittal through the developer tank. The roller-belt arrangement 2 functions to uniformly press the positive and negative sheets together to cause the transfer of an image from the negative sheet to the positive sheet. The roller-belt arrangement 2 comprises a roller 3, a pair of spaced belt rollers 4 and 5, and belt 26. The roller-belt arrangement 2 is positioned as shown in FIG. 1 by any means which can readily be supplied by one skilled in the art. The tension on the belt 26 is provided by the relative positioning of the pair of belt rollers t and 5 and also the position of roller 3. The positive sheet P and the negative sheet N as they pass through the roller-belt arrangement 2 are maintained under a pressure contact through the entire area from point 28 to point 9 which aids in providing a more uniform image on the positive sheet P. If the rotation of any of the shafts of the rollers becomes eccentric for any of a number of reasons the roller-belt arrangement still maintains a relatively uniform pressure on the sheets moving therethrough. In contrast if two engaging line contact rollers were utilized instead of the roller-belt arrangement of the invention any eccentricity in the rotation of either roller would cause a pronounced variance in the pressure maintained between the rollers as they rotate with respect to each other.

Positioned at the entrance of the developer housing 8 is a diverging guide means 18 which includes diverging guide surfaces 20 and 22. Guide means 18, as shown in FIG. 1, is formed by striking the center portion of the downward end of the guide means 18 in one direction to form guide surface 20, and by striking the two outside end portions of the downward ends of the guide means 18 in an lopposite direction to form guide surfaces 22. Of course, guide means 18 can be made by various methods known in the art, and could be made by using two plates. One plate could have a downward end portion bent in one direction, and the second its downward end portion bent in a second opposite direction, and the two plates can be joined together by welding, for example. The diverging guide means 18 extends across the width of the developer tank 10 and is positioned so as to be above the developer tank 10'. The diverging guide means 18 may be positioned as indicated, either by supports not shown, or in any manner that is known to one skilled in the art.

The diverging guide means 18 determines the direction of the paths of both the positive and negative sheets as they enter the developer liquid and insures that a sufficient amount of developer liquid will come into contact with and properly wet the positive and negative sheets before the sheets are passed through the developer tank 1t). A pair of drive rollers 3i) and 31 are shown, and these rollers are not essential to the invention, but illustrate means for driving the positive and negative sheets through the developer tank 10. The rollers 30 and 31 can be driven by a motor (not shown) or in any other manner known in the art, and can be mounted as shown by any means.

In operation, the positive sheet and negative sheet are hand-fed into the entrance slot 16, from there, into slots 17 and 19, formed by the outside guide walls 11 and 13 and the diverging guide means 18 as illustrated in FIG. 1. The positive sheet P is positioned in slot 17 on one side of the diverging guide means 18 and the negative sheet end is positioned in slot 19 on the other side of the diverging guide means 18. The particularities of guide means or entrance slots that can be utilized to aid in feeding the sheets to the diverging guide means 13 can be readily designed as required. The positive and negative sheets are hand-fed through slots 17 and 19 until they engage drive rollers 30 and 31 and thereafter, the drive rollers 36 and 31 will cause the sheets to move through the developer tank 10l up to the bite at 2.8 of the roller-belt arrangement 2. As the positive sheet and negative sheet travel with respect to the diverging guide means 18, they reach the diverging guide surfaces 2t) and 22, respectively, and their paths of travel separate and extend in diverging directions as is clearly shown in FIG. 1. The positive sheet P and the negative sheet N both have a degree of stiffness that enables the photocopy papers to travel in paths indicated in FIG. 1 above the level of the liquid. After the positive and negative sheets pass below the level of the liquid in the developer tank 10, they begin absorbing developer liquid and proceed to the bottom ribs 12 of the developer tank, and from thereon the positive sheet P and the negative sheet N are guided by gravity and the bottom ribs 12 of the developer tank 10 to the bite at 28 of the roller-belt arrangement 2.

In passing through the roller-belt arrangement 2, the positive and negative sheets are pressed int-o contact with each other between roller 3 and belt 26 all the way from the initial bite of the roller-belt arrangement at 28 to the point 9 to cause the transfer of a uniform image from the negative sheet N to the positive sheet P. The sheets then pass through the exit slot 63 in the developer housing 8 and after a short wait, the positive sheet P and the negative sheet N are separated by the operator to provide the required finished product, which is the positive print on the positive paper P.

Referring now to FIG. 2, there is illustrated a crosssectional partial side view of another embodiment of the invention that includes a developer housing 8', a developer tank 10', a plurality of parallel spaced bottom ribs 12', all as in FIG. l, and a modified diverging guide means 18. The diverging guide means 18 performs in the same manner as the guide means 18. However, the difference is that the guide means 18' illustrated in FIG. 2, can be utilized without change in the automatic apparatus of the Stuckens application entitled Photocopy Device filed on Dec. 27, 1957, bearing Ser. No. 705,520J

`outwardly by one of the diverging surfaces 20.

and can be utilized to replace all of the gui-de means in the tank except the guide means formed on the bottom of the developer tank, for guiding through the solution the positive and negative sheets shown therein and reference is directed t-o said application for a clearer understanding of FIG. 2. Otherwise, the guide means 18', illustrated in FIG. 2, performs the same function in substantially the same manner as does the guide means 18 in FIG. l. The guide means 18 may be for-med in any manner known to those skilled in the art and could be formed by the bending of one piece of metal, for example, with attention directed to obtain the pair of diverging surfaces 20 and 22.

The positive sheet P is directed from the exit end 32a of guide way 32 by 'drive means (not shown) and is fed to drive roller 60 and idler roller 61. From drive roller 60 and idler roller 61, the positive sheet P is fed into the developer tank The positive sheet P is guided in its path into the developer tank 10 by the diverging guide means 18 over its back surface 43 land from thence, The negative sheet N is delivered to drive rollers 46, 48 from the exposure means in the paper separator not shown in FIG. 2, but described in the previously mentioned Stuckens application, by drive means also not shown. From drive rollers 46 and 48, the negative sheet N is fed into the developer tank 10'. The negative sheet N is guided in its path into developer tank 10 also by the diverging gui-de means 18 over its front surface and particularly by the other diverging surfaces 22.

Other than the difference in feeding the positive and negative sheets into the developer tank 10', the embodiment of the invention illustr-ated in FIG. 2 is substantially the same as the embodiment of the invention illustrated in FIG. 1 and the previous description thereof suffices.

Referring now to FIG. 3, there is illustrated another embodiment of the invention wherein the positive and negative sheets are manually pushed through the developer liquid until their leading edges engage a modified roller-belt arrangement 21 at the exit side of the developer tank.

There is illustrated in FIG. 3 the developer housing 8", developer tank 10, the modified roller-belt arrangement 21, which will be explained, all functioning as their counter-parts in FIG. l. An entrance slot 16" is provided for the positive and negative sheet P and N respectively. A diverging guide means 18" is positioned somewhat similarly, as the guide means 18 in FIG. 1 and can be formed in a similar manner and functions in the same manner. However, mounting plate 44 is illustrated as being attached to guide means 18 and functions to slide into properly cut slots, not shown, in the housing 8 and a mounting plate 44 is positioned on each side of the guide means 18". The diverging guide surfaces 20" and 22 of guide means 18" direct positive and negative sheets in diverging paths as they are fed into the developer liquid, thereby enabling the positive and negative sheets to be properly wetted by a sufficient amount of developer liquid as they travel into and through tank 10".

The modied roller-belt arrangement 21 comprises roller 3, belt rollersv4 and 5, and belt 26 as in the roller-'belt arrangement 2 illustrated in FIGURE il. However, tube 27 has been added and is loosely positioned around and ispof a greater diameter than roller 3". Tube 27 functions to balance the speed between the belt 26 and the roller 3". Tube 27 is in friction contact with roller 3" and if for some reason belt 26" slips, the force exerted on tube 27 due to the difference in speeds between belt 26 and roller 3 causes the tube 27 to also slip to thus insure that the positive sheet and the negative sheet passing through will not be shifted one with respect to the other. Otherwise, the roller-belt arrangement 21 functions in the same manner as roller-belt arrangement 2 illustrated in FIG. 1 and described previously.

In the embodiment of the invention illustrated in FIG. 3, the operator inserts the positive and negative sheets in the ent-rance slot 16 and they are guided in slots 17 and 19" by guide walls 1'1" and 13, respectively, and guide means 18". However, no drive rollers are provided and the operator must push the positive and negative sheets through the developer liquid until the leading edges thereof engage the bite at 28" of the roller-belt arrangement 21, and from then on, the positive and negative sheets are automatically carried through the developer housing 8 in the developer tank 10" and out through the exit slot 6 in the developer housing 8".

Other details and operation are apparent from FIG. 3 and from the previous description of the embodiments of the invention illustrated in FIGS. l and 2.

What has been described is considered to be the preferred embodiments of the invention and many modications and alterations can be made without departing from the inventive scope of the invention, and it is intended that the appended claims be restricted only by the prior art.

What is claimed is:

=1. A device for developing exposed photographic sheet material and for transferring an image onto an unexposed transfer sheet material by moistening the materials with a developer liquid and by subsequently pressing the materials into Contact one with the other, said device comprising a developer tank arranged to hold developer liquid therein at a given level, an arrangement of roller pressing means comprising a lroller-belt arrangement positioned adjacent the exit end of said developer tank for pressing said materials into an extended plane of contact with one another, and guide means including two surfaces forming an angle therebetween and positioned adjacent the opposite end of said developer tank and arranged above the level of the liquid for directing said sheet materials in diverging paths into the liquid in said developer tank whereby said sheet materials will be wetted with a suflicient amount of developer liquid before coming into contact with each other, the bottom of the developer tank being arranged to guide both the sheet materials only after they have come into contact with each other and to direct said sheets to the point of tangency of said rollers.

2. A device for developing exposed photographic sheet material and for transferring an image onto an unexposed transfer sheet material by moistening the materials with a developer liquid and by subsequently pressing the materials into contact one with the other, said device comprising a developer tank adapted to hold developer liquid therein at a given level, an arrangement of roller pressing means comprising a roller-belt arrangement positioned adjacent the exit-end of said developer tank for pressing said materials into an extended plane of contact with one another, said roller-belt arrangement comprising a rotating belt positioned over a pair of spaced -belt rollers and driven thereby and a main driven roller positioned adjacent said belt and in contact therewith to provide tension between said belt and said main roller over an extended plane, and guide means comprising a lirst surface, a second surface and a third surface, said second surface and said third surface forming an angle with each other and with said rst surface, said guide means positioned adjacent the end of said developer tank opposite the rollerbelt arrangement and arranged above the level of the liquid for directing said sheet materials in diverging paths into the liquid in said developer tank whereby said sheet materials will be wetted with a sufficient amount of developer liquid before coming into contact with each other, the bottom of said developer tank being arranged to guide both said sheet materials only after they have come into contact with each other and to direct said sheets to the point of tangency of said roller-belt arrangement.

3. A device for developing exposed photographic sheet material and for transferring an image onto an unexposed transfer sheet material by moistening the materials with a developer liquid and by subsequently pressing the materials into contact one with the other, said device comprising a developer tank adapted to hold the developer liquid therein, contacting pressure means comprising a roller-belt arrangement position adjacent the exit end of said developer tank for pressing said materials into an extended plane of contact with one another, said roller-belt arrangement comprising a rotating belt positioned over a pair of spaced belt rollers and driven thereby and a main driven roller positioned adjacent said belt and in contact therewith to provide tension between said belt and said main roller over an extended plane, a guide means including two surfaces forming an angle therebetween and positioned adjacent the opposite end of said developer tank and arranged above the level of the liquid for directing said sheet materials into initially diverging paths above the level of the liquid before immersion in the liquid in said developer tank whereby said sheet materials will be wetted with a sufiicient amount of developer liquid before coming into contact with each other, the bottom of said developer tank being arranged to guide both -the sheet materials only after they have come into contact with each other and to direct such sheets to the point of engagement of said contacting roller-belt arrangement.

4. IIn a device as in claim 3, wherein the bottom of said developer tank has formed thereon a plurality of spaced parallel substantially U-shaped ribs.

5. A device for developing exposed photographic sheet material and for transferring an image onto an unexposed transfer sheet material by moistening the materials with a developer liquid and by subsequently pressing the materials into contact one with the other, said device comprising a developer tank adapted to hold developer liquid therein, contacting pressing means comprising a rollerbelt arrangement positioned adjacent the exit end of the developer tank for pressing said materials into an extended plane of contact with one another, said roller-belt arrangement comprising a rotating belt positioned over a pair of spaced belt rollers and driven thereby and a main roller assembly comprising a driven main roller having a tube of a greater diameter positioned therearound and -in contact with said belt and said main roller whereby tension is maintained between said tube and said belt over an extended plane and where slippage of said belt will cause slippage of said tube, and guide means comprising a first surface, a second surface and a third surface, said second surface and said third surface forming an angle with each other and said first surface, said guide means positioned adjacent the opposite end of said developer tank and arranged above the level of the liquid for directing said sheet materials in initially diverging paths above the level of the liquid before immersion in the liquid in said developer tank whereby said sheet materials will be wetted with a sufficient amount of developer liquid before coming into contact with each other at the bottom of the tank, the bottom of said developer tank being arranged to guide both sheet materials only after they have come into contact with each other and to direct said sheets to the point of engagement by said contacting roller-belt arrangement.

6. In a photocopy machine adapted to carry out the diffusion-transfer process the combination of;

a tank;

said tank having a bottom contoured to hold a quantity of developer fluid through which positive and exposed negative photographic sheets may be passed;

said bottom of said tank having,

a first portion extending downwardly and inwardly at the entrance side thereof,

a second portion extending upwardly and outwardly at the exit side thereof, and

a substantially fiat intermediate area covering a substantial portion of the bottom and disposed substantially horizontally;

an arrangement of roller pressing means positioned above said exit side of said tank so that the leading edges of said photographic sheets passing through the developer fluid will be guided therto by said second portion of said bottom;

said first portion of said bottom `defining first guide means for guiding one of said sheets into the fiuid; and

second guide means for guiding the other of said sheets into the fluid and for maintaining them separated until they are wet by the fluid consisting of separator means at the entrance side of said bottom.

7. In a photocopy machine adapted to carry out the diffusion-transfer process the combination of a tank;

said tank having a bottom contoured to hold a quantity of developer fluid through which positive and exposed negative photographic sheets may be passed;

said bottom of said tank having,

a first portion extending downwardly and inwardly at the entrance side thereof,

a second portion extending upwardly and outwardly at the exit side thereof, and

a substantially fiat intermediate area covering a substantial portion of the bottom and disposed substantially horizontally;

an arrangement of roller pressing means positioned above said exit side of said tank so that the leading edges of said photographic sheets passing through the developer fiuid will be guided thereto by said second portion of said bottom;

said first portion of said bottom defining first -guide means for guiding one of said sheets into the fluid; and

second guide means for guiding the other of said sheets into the iiuid and for maintaining them separated until they are wet by the liuid consisting of separator means at the entrance of said bottom;

said separator means arranged above the level of said developer fiuid and provided with diverging surfaces for directing the photographic sheets passing thereover into diverging paths above the level of said developer fluid before immersion in the developer fluid.

8. In a photocopy machine adapted to carry out the diffusion-transfer process the combination of:

a tank;

said tank having a bottom contoured to hold a quantity of developer iiuid through which positive and exposed negative photographic sheets are passed moving from one side to the opposite side of the tank;

said bottom of said tank having,

ia first portion extending downwardly and inwardly from said one side thereof,

a second portion extending upwardly and outwardly toward said opposite side thereof, and

a flat intermediate area interconnecting said irst and second portion and extending generally horizontally for a substantial portion of said bottom;

an arrangement of roller pressing means positioned above said opposite side of said tank so that leading edges of said photographic sheets passing through the developer uid will be guided thereto by said second portion of said bottom;

said first portion of said pottom defining first guide means for guiding one of said sheets into said iiuid;

second guide means consisting of separator means by said first portion of said bottom for -guiding the other of said sheets into the iiuid and for maintaining the sheets separated until they are wet by the fluid; and

the interior of said tank being unobstructed at all portions thereof from the plane of the separator means to said roller pressing means wherein any obstruction would be eiective Ito holdsaid last mentioned sheet in said fluid during movement thereof from said separator means to said roller pressing means.

9. ln a photocopy machine adapted to carry out the diffusion-transfer process the combination of:

a tank for holding a quantity of developer fluid through which positive and exposed negative photographic sheets are passed moving from one side to the opposite side of the tank;

a sheet supporting surface in said tank extending between said sides of said tank;

said sheet supporting surface having,

a first portion extending downwardly and inwardly from said one side,

a second portion extending upwardly and outwardly toward said opposite side, and

a ilat intermediate area interconnecting said first and second portions -and extending generally horizontally for a substantial portion of said surface;

an arrangement of roller pressing means positioned above said opposite side of said tank so that leading edges of said photographic sheets passing through the developer iluid will be guided thereto by said second portion of said surface;

said iirst portion of said surface deiining rst guide means for guiding one of said sheets into said uid;

second guide means consisting of separator means adjacent said rst portion of said surface for guiding the other of said sheets into the fluid and for maintaining the sheets separated until they are wet by the fluid; and

the interior of said tank being unobstructed at all portions thereof from the plane of the separator means to said roller pressing means wherein any obstruction would be effective to hold said last mentioned sheet in said fluid during movement thereof from said separator means to said roller pressing means.

10. A device for developing exposed photographic sheet material and for transferring an image -onto an unexposed transfer sheet material by moistening the materials with a developer liquid and by subsequently pressing the materials into contact one with the other, said device comprising a developer tank adapted to hold developer liquid therein, a roller-belt arrangement positioned adjacent the eXit and of said developer tank for pressing said materials int-o an extended plane of contact With one another, and guide means positioned adjacent t-he Opposite end of said developer tank and arranged above the level of the liquid for directing said sheet materials in diverging paths into the liquid in said developer tank whereby said sheet materials will be wetted with a sufcient amount of developer liquid before coming into contact with each other, the bottom of said developer tank arranged to guide both said sheet materials only after they have come into contact with each other and to direct said sheets to the point of tangency of said roller-belt arrangement, the bottom of said developer tank having positioned therein a plurality of spaced substantially U-shaped ribs.

References Cited by the Examiner UNITED STATES PATENTS 2,792,768 5/ 1957 Ludwig 95-89 2,841,080 7/1958 Viscardi lOl-178 2,986,987 6/ 1961 Limberger 95-89 FOREIGN PATENTS 1,105,003 6/1955 France.

315,620 10/ 1956 Switzerland.

NORTON ANSHER, Primary Examiner. D. B. LOWE, C. B. PRICE, Assistant Examiners.7 

10. A DEVICE FOR DEVELOPING EXPOSED PHOTOGRAPHIC SHEET MATERIAL AND FOR TRANSFERRING AN IMAGE ONTO AN UNEXPOSED TRANSFER SHEET MATERIAL BY MOISTENING THE MATERIALS WITH A DEVELOPER LIQUID AND BY SUBSEQUENTLY PRESSING THE MATERIALS INTO CONTACT ONE WITH THE OTHER, SAID DEVICE COMPRISING A DEVELOPER TANK ADAPTED TO HOLD DEVELOPER LIQUID THEREIN, A ROLLER-BELT ARRANGEMENT POSITIONED ADJACENT THE EXIT AND OF SAID DEVELOPER TANK FOR PRESSING SAID MATERIALS INTO AN EXTENDED PLANE OF CONTACT WITH ONE ANOTHER, AND GUIDE MEANS POSITIONED ADJACENT THE OPPOSITE END OF SAID DEVELOPER TANK AND ARRANGED ABOVE THE LEVEL OF THE LIQUID FOR DIRECTING SAID SHEET MATERIALS IN DIVERGING PATHS INTO THE LIQUID IN SAID DEVELOPER TANK WHEREBY SAID SHEET MATERIALS WILL BE WETTED WITH A SUFFICIENT AMOUNT OF DEVELOPER LIQUID BEFORE COMING INTO CONTACT WITH EACH OTHER, THE BOTTOM OF SAID DEVELOPER TANK ARRANGED TO GUIDE BOTH SAID SHEET MATERIALS ONLY AFTER THEY HAVE COME INTO CONTACT WITH EACH OTHER AND TO DIRECT SAID SHEETS TO THE POINT OF TANGENCY OF SAID ROLLER-BELT ARRANGEMENT, THE BOTTOM OF SAID DEVELOPER TANK HAVING POSITIONED THEREIN A PLURALITY OF SPACED SUBSTANTIALLY U-SHAPED RIBS. 